Inclosed switch.



A. K.SUTHERLAND.

lNc'LosED SWITCH.

APPLICATION FILED NOV. 5, l9l.

A. K. SUTHERLAND. ,NcLosEo swlcH.

V APPLICATION FILED NOV. 5.1917. 1,281 ,872. n Patented 001;. 15, 1918.

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UNITED STATES PATENT OFFICE.

ALEXANDER E. SUTHEELAND, or NEW BRITAIN, CONNECTICUT, AssIGNoE To THE TEUMEULI. ELECTRIC MEG. Co., or PIAINVIILE, CONNECTICUT, A CoEroEATIoN CE CONNECTICUT.

INCLOSEDr SWITCH.

Specification of Letters Patent.

Patented Oct. 15, 1918.

Application filed November 5, 1917. Serial No. 200,235.

Switch, of which the following is a specification.

This invention relates to switches of the inclosed type, and the ob'ects of the invention are to prevent unaut orized xtamperincr with the switch and to necessitate opening df the switch before the switch casing can be opened.

Other objects are toretain the switch in the circuit-open position when the switch casing is open, but at the same time to permit one authorized in the handling of the switch to throw the switch to circuit-closed position even when the cover isopen. Another object is to provide` simple and imroved locking mechanism for the cover.

hese objects, I `have attained yby providing a lockfor the coverof the switch casing, which when the cover is closed, with the switch in circuit closed position, locksthe cover in such position and ldoes not interfere with the opening and closing movements of the switch, but which, when the cover is open, is projected intoa position where it stops the switch from being thrown to the circuit-closed position. v

Other features of the invention and the details of construction will appear as the specification proceeds. In the accompanying drawings, I have illustrated the invention embodied in a practical and preferred form, but I would have it understood that these disclosures are illustrative in character and that changes and modifications may be made Without departure from the true spirit and scope of `the invention. r

In said drawings Figure 1 is a plan view, showing the cover entirely open.

Fig. 2 is a side View, showing the switch operatinghandle in the switch-closed position, and indicating lthe open-circuit position of the handle in ydotted lines.

Fig. 3 is a broken plan view,similar to Fig. 1, illustrating how the cover lock acts as a stop to prevent switch closing movement, when the cover is open.

Fig. 4 is a sectional View taken substan tially on the plane of the line 4--4 of Fig. 1..

F1g. f is a cross sectional view taken substantially on the plane of the line 5-5 of Fig. 1, showing the cover and switch both in their closed positions.

Fig. 6 is a similarview with the cover open and the switch locked in open-circuit position.

The switch, indicated at 7, may be of any usual or preferred construction and as illustrated is of the knife blade type, having a movable switch element embodying knife blade contacts 8, connected by cross bar 9,

for engagement with the stationary con-` tacts 10. l The switch is mounted within a casing or inclosure comprising a box-like structure 11, having a movable cover 12, which is shown hingedto the box at one end at 13.

The switch operating means comprises an external handle 14C journaled to oscillate at 15 in one of the side Walls of the box, and connections at the inside-ofthe box, embodying a ybar 16, secured to the hub of the handle and provided with a laterally extending arm 1.7,con`nected with a rearwardly eX- tending arm 18 on the cross bar of the movable switch element. A snap action of the switch is obtained in the form' illnstrated,by providing a spring connection 19 betweenthe laterally extending arm 17 and cross bar 9,

and by providing the laterally extending of the side wall of the bof; into position to engage in a, locking seat or recess 26 in the dependent rim or flange .27 of the cover.

Iny Fig. 5, the locking member is shown forced outwardly into position to engage in the locking ,recess inthe cover by means of a spring 28. This vien7 furthermore, shows how the upper edge of this recess acts as a stop, engaging the upper side of the locking lug to limit the out-movement of such locking lug and lthus prevent it from projecting into the path of movement of the operating handle in this closed position of the cover.

When the cover is open, as illustrated in Fig. 6, the locking member is no longer held in retracted position and so is projected by the spring 28 to a point where the locking lug stands in the path of switch closing movement of the operating handle. See also in this connection, Fig. `3, which shows4 clearly how, in this open position of the cover, the locking member serves as a stop to prevent switch-closing movement of the operating mechanism..

The locking mechanism is retracted to' permit opening of the cover by means consisting, in the present disclosure, of a retracting lever 29, disposed behind the upstanding portion of the locking member and having an angularly projecting lug 30, en'- gaged in an opening 31 provided therefor in the upper portion of the locking member. Therearward end portion of the retracting lever is inclined inwardly into the box and is engaged beneath the bar 16, as shown at 82. This inclined portion 32, as it is en gaged by the bar 16 in the switch opening movement, acts'in the capacity of a lever arm, causing the member 29 to fulcrum on the point of bend therein at 83 and so retract the lock, as shown in Fig. 1, and thus releases the cover. If, in this open position of the cover, it is attempted to close' the switch, the locking lug is immediately projected in the path of the switch operating handle, as shown in Fig. 3.

In some instances, an expert or one authorized to use the switch may wish to close the switch when the cover is open, for instance `for testing the operation of the switch. This is provided `for in my -invention, by reason of the fact that the locking lug 2l which projects into the path of movement of the switch operating handle may be pushed inwardly with the fingers to free it from the handle. j

The retracting lever is supported at its forward end by its engagement in the opening in the locking member and, at its rearward portion, by riding on the rim of the washer 34 which is engaged on the journal of the operating handle, as shown in Fig. 4.

The structure disclosed is relatively simple and inexpensive and forms both a secure lock for the c over and a reliable safety device for preventing' unauthorized closing of the switch when the cover is open.

'I claim: Y

1.v In combination, a switch embodying a Inovable switch element, an inclosure for said switchlhaving a hinged cover, operatingmeans for the switch outside the inclosure and connected with the movable switch element within the inclosure, a hook engageable with the cover for lockin the cover in closed position, a retracting lgever operable on the switch opening movement of the operating member for retracting said hook to enable opening of the cover, means for projecting the locking hook into the path of switch closingv movement of the operating member when the cover is open whereby said hook will form a stop preventing closing ofthe switch when the cover is open, and means for reventing the locking hook from stopping t e operating member when the lcover is closed.

2. In combination, a switch having a movable. switch element, a box inclosing the switch having a hinged cover, a hook-shaped latch mounted in the box, said cover having a locking recess to receive the point of said latchand to limit the outward movement of the latch, an operating handle mounted outside the box andconnected with the movable for the switch having a hub portion jour-f naled in one side of the box, a bar secured to said hub portion inside of the box` andconnected with the movable switch element, a spring-pressed locking member mounted in the box and provided'with an outwardly projecting locking lug for engagement with the cover, said cover having a locking recess to receive said lug, and a lockretracting lever connected with the lockin memb er and having an angularlydispose leverage portion engaged beneath the bar, which is connected wlth the hub of the operating handle so as to be operated thereby.,

ALEXANDERv K. SUTHERLAND. j 

